Abnomal nitrogen metabolism is often observed in hepatic diseases such as liver cirrhosis and renal diseases such as chronic renal failure. There has not been effective medicines for such symptom. In a mild case, dietetic therapy has been applied and when the symptom progresses, fluid therapy has been applied by administrating infusion fluid containing amino acids mixture.
Various infusion fluids containing amino acids have been known. For example, an amino acids infusion fluid for cancer patients is disclosed in Japanese Unexamined Patent Application Gazette No. 55 (1980)-35049. The infusion fluid disclosed in this reference contains all of 8 kinds of essential amino acids for closely imitating the composition of plasma amino acids of a healthy human.
To liver cirrhosis patients it is recommended in Japanese Unexamined Patent Application Gazette No. 56(1981)-27493 to administrate an infusion fluid containing amino acids which are generally deficient in liver cirrhosis in order to recover normal amino acids composition in blood of a healthy human. In Japanese Unexamined Patent Application Gazettes Nos. 55(1980)-36457 and 54(1979)-26324, infusion fluids for liver cirrhosis patients containing relatively larger parts of branched chain amino acids such as leucine, isoleucine and valine and relatively smaller parts of tyrosine and phenylalanine.
The conventional amino acids infusion fluids can be expected to have temporary effects, however, it has been a question whether the conventional infusion fluids may actually improve nitrogen metabolism for a long period of time.
The inventors of the present invention have extended their efforts for seeking a simple composition of amino acids which can be orally administered to patients of hepatic and renal diseases on the view points that:
(1) Aspartic acid and alanine will be necessary to supplement metabolic pool of amino acids and to promote internal formation of albumine by glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT). PA1 (2) Glycine will be necessary to be bonded with aromatic amino acids so as to produce hippuric acid which can be excreted in urin, since benzene rings of aromatic amino acids can be hardly decomposed. PA1 (3) Glycine will be also necessary for the reason that synthesis of haemoglobin can be promoted by incorporateing free irons in body fluids in porphirin rings formed by bonding of carbonic acids of glycine and carbonyl group of succinic acids. PA1 (4) Crystine will be necessary as a donor of methyl radical for the purposes described in the above items (1) and (3).
As the results, the inventors of the present invention found a new composition of amino acids which is effective for increasing serum albumin, haemoglobin and branched chain amino acids and for improving nitrogen metabolism for a long period of time. The present invention is based on this discovery.